Internal-combustion engine provided with an auxiliary charging pump



' J. FREISLINGER INTERNAL" comausnon ENGINE PROVIDED WITH AN AUXILIARY cmeme PUMP Filed Feb. 9. 1926 2 11 Uentor:

Patented Mar. 20, 1928.

UNITED- STATES PATENT orrlcs.

JOSE! FREISLINGER, OF VIENNA, AUSTRIA.

Application flled l'ebruary 9, 1926, Serial No. 86,978, and in Austria February 16, 1925.

This invention relates to an internal combustion engine provided with an auxiliary charging pump, in which before the beginning of the. com ression stroke a supplementary charge (in or mixture) is forced into the air or mixture of fuel and air, al ready contained in the working cylinder, by means of the auxiliary charging pump.

The engine according to the present invention possesses also the economical advantages of a construction in which the working chamber is rendered adjustable by the provision of an auxiliary piston The essential feature of the present invention consists in that each working piston and the auxiliary piston are surrounded or enclosed by a sleeve valve, which valves control the working cylinder, the pump and the inlet for admitting the auxiliary'charge.

One mode of carrying outthe present invention is illustrated by way of example on the accompanying sheet of drawings in which-- Fig. 1 shows a four stroke engine in gitudinal section.

lon- Fig. 2 is a longitudinal section through the casing with the control of the auxiliary piston in elevation and the cover of the easing removed.

Figs. 3 and 4 are sectional views ofthe casing, the sections being taken on lines III-III and IVIV respectively of Figs. 1 and 2. F

The cylinder casing 1, 2 is closed by covers 3, 4 and 5, and sleeves or liners 6 and 7, to which auxiliary pistons 8 and 9 respectively are secured, are movably arranged in the casing. Screw-threadedholes 10 and 11 respectively, provided in the heads of pistons 8-9, serve for the attachment of sparking plugs. The sleeves 6 and 7 with .the auxiliary pistons 8 and 9 are operated by oscillating levers 14 and 15 respectively, whose pins rest in bearings 16 and 17. Sliding members 18 and 19 are arranged on the oscillating levers 14 and 15 and their pins are led in guides 20 and 21 respectively. The guides, consisting of slides, are mounted reciprocably in the cover 3 or in the casing and, sas shown by the lines A-B and C -D lutions of the latter by means of toothed wheels 27 and 28. The auxiliary pistons 8, 9 and the working pistons 12, 13 are surrounded by a pair of sleeve valves. The inner sleeve valves 29 and 30 are operated by connecting rods 31 and 32 respectively and the outer tubular slides 33 and 34 are driven by connecting rods 35 and 36, the said rods being operated by the shaft 24, whereby the outer sleeve valves 33, 34 are in advance of the inner sleeve valves 29, 30. Each pair of sleeve valves controls the correspondin cylinder andis provided with admission and exhaust ports at'the end of the sleeve disposed adjacent to the combustion chamber as Well as at the end of the sleeve disposed adjacent to the crank-casing. In the illustrated embodiment the time of opening and closing the ports of the pairs of valves 29, 33 and 30, 34 respectively, disposed adjacent to the combustion chamber, are displaced to each other for twostrokes. During the first stroke, the Working cylinder sucks in air or a mixture of fuel and air through the admission channels 37 and 38 as well as through the admission ports of the pairs of sleeves 29, 33 and 30, 34 arranged at the side-of the combustion chamber during the inward stroke of the working piston 12 and 13 respectively. As soon as the workin pistons 12 and 13 have passed the inner dea centre position, the pair of sleeves 29, 33 and 30, 34 respectively close the admission channels 37 and 38 respectively and uncover the slot of a 'by-pass channel 43, disposed atthe crank-side, which establishes communication between the crank-casing and the working cylinder, so that atthe beginning I of the compression an auxiliary charge is added to the cylinder-charge. As soon as this auxiliary charge is admitted, the acting sleeve valve of the working cylinder closes the slot of the bypass channel and now commences the second stroke, the compression by the working pistons 12' and 13, whereby air ora mixture of fuel and air is simultaneously sucked into the crank-casing. Thereby the auxiliary piston 8 and 9 respectively limits the corresponding compression 'or combustion space. As soon as the desired compression has been accomplished, ignition takes place at 10 and 11 by means of the spark plugs. Now follows the third stroke, the expansion of the gases of combustion, whereby during the inward motion the working pistons 12 and 13 compress the charge in the crank casing already sucked in behind the same, in order that the same can be supplied as next auxiliary charge into the corresponding working cylinder in the described manner. The charge of the crank casing is effected during the outward motion of the working pistons 12 and 13 by way of the openings 39, 40, which are controlled also by the sleeve valves The exhaust takes place by way of the opening 41. 42, which are controlled by the sleeve valves. If the working pistons 12, 13 move to the inner dead centre position during the suction stroke, thus toward the crank casing, the auxiliary pistons 8, 9 closing up the corresponding combustion chamber moved outward and increase the effect of suction by increasing the contents of the cylinder. After compression and ignition the auxiliary pistons 8, 9 move inward, thus toward the crank casing, and reach their in-' nermost pbsition at the end of the exhaust stroke. Thereby thehead of the auxiliary piston comes very close to the -head of the working piston, so that the gases of combustion are completely pushed out of the cylinder. The stroke of the auxiliary pistons is adjustable in order to regulate the compression-chamber. The stroke is adjusted by raising or lowering the guide-slides 20 and 21. in which the sliding members 18 and 19 of the oscillating levers 14 and 15 respectively are rotatably mounted by means of pins. As shown in Fig. 2. the slides 20 and 21 are inclined to each other, whereby during the adjustment of the stroke the innor dead centre position of the auxiliary piston is maintained and only the outer dead centre position is varied according to requirement. The present invention is just as well'applicable to two stroke engines'or to engines working with any other kind of strokes.

I claim- 1. In an internal combustion engine, a combustion cylinder provided with intake and exhaust ports'and an auxiliary intake port, a working piston operating in said cylinder, an auxiliary piston in said cylinder, a pair of sleeve valves surrounding said pistons and con rolling said ports, and means for \arying th throw of the auxil-- are iary piston with relation to the throw of the working piston.

2. In an internal combustion engine, a

combustion cylinder provided with intake and exhaust ports and an auxiliary intake port, a working piston operating in said cylinder, anauxiliary piston in said cylinder, a pair of sleeve valves surrounding said pistons and controlling said ports, an actuating shaft driven from the crank shaft of the engine, means operated by the actuating shaft for reciprocating the auxiliary piston and sleeve valves, and means for varying the throw of the auxiliary piston with relation to the throw of the working piston. 3. In an internal combustion engine, a combustion cylinder provided with intake and exhaust ports and an auxiliary intake port, aworking piston operating in said cylinder, an auxiliary piston in said cylinder, a pair of sleeve valves surrounding said pistons and controlling said ports, and means for operating the auxiliary piston and the sleeve valves in timed relation to each other and to the working piston.

4. In an internal combustion engine, a combustion cylinder provided with intake and exhaust ports and an auxiliary intake port, a working piston operating in said cylinder, an auxiliary piston in said cylinder, a pair of sleeve valves surrounding said pistons and controlling said ports, means for operating the auxiliary piston and the sleeve valves in timed relation to each other and to the working piston, and means for varying the throw of the auxiliary piston with relation to the throw of the working piston.

5. In an internal combustion engine, a combustion cylinder provided with intake and exhaust ports and an auxiliary intake port, a working piston operating in said cylinder, an auxiliary piston in said cylinder, :1 pair of'sleeve valves surrounding said pistons and controlling said ports, a shaft driven from the engine shaft, means actuated by said shaft for operating said sleeve valves, an oscillating arm connected with the auxiliary piston, and an eccentric on said shaft operatively coupled to said arm.

6. In an internal combustion engine, a

combustion cylinder provided with intake and exhaust ports and an auxiliary intake port, a working piston operating in said cylinder, an auxiliary piston in said cylinder, a pair of sleeve valves surrounding said pistons and controlling said ports, a shaft driv en from the engine shaft, connecting means between said shaft and said sleeve valves for operating the latter, a sleeve connected with the auxiliary piston, an oscillating arm connected with said sleeve, and an eccentric on said shaft and coupled to said arm.

7. In an internal combustion engine, a combustion cylinder provided with intake and exhaust ports and an auxiliary intake 3 port, a working piston operating in said ciated with the operating means for the auxcylinder, an auxiliary piston in said cyliniliary piston for varying the action of said de1','a pair of sleeve valves surrounding said 'operatlng means and accordingly varying l0 pistons and controlling said ports, means for the throw of the auxiliary piston with rela- 8 operating said valves and said auxiliary pistion to the throw of the working piston.

ton in timed relation to each other and t0 the In testimony whereof I afiix my si ature. working piston, and adjusting means asso- JOSEF FREISLIN ER. 

